This study is a continuation of work to validate noninvasive techniques to measure biologically meaningful levels of reproductive and adrenal steroid hormones in feces of captive-maintained baboons. Results will serve to establish the general validity of these techniques for use on a variety of species in captivity and the field. Captive studies are: 1) identifying fecal and urinary metabolities of estradiol (E2), progesterone (P4), cortisol (C), dehydroepiandosterone (DHEA), and testosterone (T), as well as respective excretion rates after radiolabel infusion; (2) developing indices of nonspecific steroid excretion rate, particularly those associated with GI transit time; 3) testing the influence of dietary fiber on fecal steroid excretion rate, and the potential of eliminating existing effects using nonspecific excretion rate indices; 4) correlating longitudinal fecal steroid excretion profiles with blood hormone secretory patterns, urinary metabolite excretion, and visual markers (e.g. menses and sex skin turgescence) during natural reproductive cycles and, in the case of C and DHEA, after acute challenges with exogenous ACTH; 5) determining if fecal P4 excretion following time-mating is useful indicator of early pregnancy or spontaneous abortion. These excreted steroid techniques are likely to provide an important noninvasive tool for interrelating reproductive function and adrenal activation with naturally and/or artificially occurring socio-ecological events.